NASA News Digest: Space Science For 23 June – 10 July 2014

The NASA News service provides up-to-date announcements of NASA policy, news events, and space science. A recent selection of space science articles are provided below, including direct links to the full announcements. Those interested in receiving these news announcements directly from NASA can subscribe to their service by sending an email to:

NASA’s Mars Curiosity rover will complete a Martian year — 687 Earth days — on June 24, having accomplished the mission’s main goal of determining whether Mars once offered environmental conditions favorable for microbial life.

One of Curiosity’s first major findings after landing on the Red Planet in August 2012 was an ancient riverbed at its landing site. Nearby, at an area known as Yellowknife Bay, the mission met its main goal of determining whether the Martian Gale Crater ever was habitable for simple life forms. The answer, a historic “yes,” came from two mudstone slabs that the rover sampled with its drill. Analysis of these samples revealed the site was once a lakebed with mild water, the essential elemental ingredients for life, and a type of chemical energy source used by some microbes on Earth. If Mars had living organisms, this would have been a good home for them.
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For more information about Curiosity, visit:www.nasa.gov/msl and mars.jpl.nasa.gov/msl/

Ocean on Saturn Moon Could be as Salty as the Dead Sea

Scientists analyzing data from NASA’s Cassini mission have firm evidence the ocean inside Saturn’s largest moon, Titan, might be as salty as the Earth’s Dead Sea.

The new results come from a study of gravity and topography data collected during Cassini’s repeated flybys of Titan during the past 10 years. Using the Cassini data, researchers presented a model structure for Titan, resulting in an improved understanding of the structure of the moon’s outer ice shell. The findings are published in this week’s edition of the journal Icarus.
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For more information about Cassini, visit www.nasa.gov/cassini and saturn.jpl.nasa.gov.

Testing Completed on NASA’s James Webb Space Telescope Backplane

NASA’s James Webb Space Telescope has reached another development milestone with the completion of static load testing of its primary mirror backplane support structure (PMBSS) moving the telescope one step closer to its 2018 launch.

The PMBSS is the stable platform that holds the telescope’s science instruments and the 18 beryllium mirror-segments that form the 21-foot-diameter primary mirror nearly motionless while the telescope peers into deep space. The primary mirror is the largest mirror in the telescope — the one starlight will hit first.
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For more information about NASA’s James Webb Space Telescope, visit: www.nasa.gov/webb

NASA’s Hubble Space Telescope has photographed an unusual structure 100,000 light years long, which resembles a corkscrew-shaped string of pearls and winds around the cores of two colliding galaxies.

The unique structure of the star spiral may yield new insights into the formation of stellar superclusters that result from merging galaxies and gas dynamics in this rarely seen process.

“We were surprised to find this stunning morphology. We’ve long known that the ‘beads on a string’ phenomenon is seen in the arms of spiral galaxies and in tidal bridges between interacting galaxies. However, this particular supercluster arrangement has never been seen before in giant merging elliptical galaxies,” said Grant Tremblay of the European Southern Observatory in Garching, Germany.
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For images and more information about Hubble, visit: www.nasa.gov/hubble and hubblesite.org/news/2014/26.

NASA Spacecraft Observes Further Evidence of Dry Ice Gullies on Mars

Repeated high-resolution observations made by NASA’s Mars Reconnaissance Orbiter (MRO) indicate the gullies on Mars’ surface are primarily formed by the seasonal freezing of carbon dioxide, not liquid water.

The first reports of formative gullies on Mars in 2000 generated excitement and headlines because they suggested the presence of liquid water on the Red Planet, the eroding action of which forms gullies here on Earth. Mars has water vapor and plenty of frozen water, but the presence of liquid water on the neighboring planet, a necessity for all known life, has not been confirmed. This latest report about gullies has been posted online by the journal Icarus.
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For more information about HiRISE, visit: hirise.lpl.arizona.edu